Experiment 0 - Introduction

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Experiment # 0
Introduction
The purpose of this experiment is to introduce you to the lab equipment available for
your use.
The main piece of equipment you will use in this lab is the trainer kit. Its front panel is
divided into several sections that you will need to become familiar with.
1. The main trainer kit:
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KL-300 Main Unit
(1)&(2) Fixed &
Variable DC Power
Supply
(4) Variable Clock
Generator
(5) Standard
Frequency
Generator
(6) &(7) Data
Switches
(8) Pulser Switches
(9) Thumbwheel
Switches
(10) Seven-Segment
Displays
(11) Logic Indicators
(12) Speaker
(13) Logic Probe
(14) Removable
Breadboard
Voltage values: +5V, -5V, +12V and -12V
Voltage range: +1.5V ~ +15V, -1.5V ~ -15V
Six frequency ranges:
1Hz to 10Hz
10Hz to 100Hz
100Hz to 1kHz
1kHz to 10kHz
10kHz to 100kHz
100kHz to 1MHz
Output level: independent and simultaneous TTL and CMOS,
CMOS output range adjustable from +1.5V to +15V. Fanout:
10 TTL loads
Preset frequencies:
1Hz, 50/60Hz, 1MHz, Output level: independent and
simultaneous TTL and CMOS, CMOS output range adjustable
from +1.5V to +15V Fanout: 10 TTL loads
Two 8-bit DIP switches giving 16-bit TTL level output
Four toggle switches, each with debounce circuit, TTL and
CMOS outputs
Fanout: 10 TTL loads
Two sets, each having debounced TTL and CMOS, Q and /Q
outputs
Fanout: 10 TTL loads
Two-digit, BCD code output, common point input
Four sets of independent 7-segment displays, with BCD, 7segment decoder/driver and decimal point input terminal, input
with 8-4-2-1 code
16 sets of independent LEDs, indicating high and low logic
states Input impedance: <100kW
8W, 0.25W speaker with driver circuit
TTL and CMOS level, 3mm LED displays indicate high and
low logic states
1680 interconnected tie points, accepting all DIP devices,
components with leads and solid wires of AWG #22-30
(0.3mm to 0.8mm)
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Integrated Circuits (Chips):
Integrated Circuits are usually called ICs or chips. They are complex circuits which have
been etched onto tiny chips of semiconductor (silicon). The chip is packaged in a plastic
holder with pins spaced on a 0.1" (2.54mm) grid which will fit the holes on stripboard
and breadboards. Very fine wires inside the
package link the chip to the pins. The pins are
numbered anti-clockwise around the IC (chip)
starting near the notch or dot. The diagram
shows the numbering for 8-pin and 14-pin ICs,
but the principle is the same for all sizes.
each IC has a different number on its cover, and using this number data sheets are
available to describe the function of certain IC and all of its other properties. For example
the IC 74LS00 is a quadratic two input NAND gate, and the 7402 NOR gates.
The data sheets for these two gates and others can be found on the course web site. Note
that the pin configuration for the two integrated circuits is different.
You will find that some of the ICs that we use are so-called "quad packs", meaning that
each contain four independent gates. We will only need to measure one of the gates in
each IC. ICs are classified into logic families according to their internal digital design,
two main classes of these families that will be used in this lab are TTL and CMOS.
Breadboard Description:
The breadboard has 8 sets of rows, consisting of 25 holes that are horizontally
interconnected, and groups of columns , consisting of 5 holes that are vertically
interconnected. The rows and columns are used to hold chips and wires, and interconnect
them. The connection pattern used in the breadboard is shown in the following figures.
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Connection pattern used in the breadboard
The connection pattern used in the breadboard is shown in the above Figures.
The top and bottom rows can be used to distribute +5VDC and ground to the Ics. Note
that the top and bottom “bus” rows have a break in the very middle! If you want a power
or ground bus to run the length of the breadboard, you must insert a jumper in the middle
of the row to join the two half rows together. This makes your wiring less crowded, and
makes it easy to see power and ground connections.
Good wiring.
Bad wiring.
Data switches:
In order to verify the operation of a gate it is necessary to
measure the output for all possible combinations of inputs.
We will use a 5 V DC power supply and a single ground
connection to power the IC. The logic switches, are used to
provide both a logic 0 output and a logic 1 output to drive the
circuits you will design and build. They provide a voltage of
zero volts (ground) for logic 0, and either +5V or other
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voltage settings for logic 1.It is important to note that for logic inputs we must use either
5 V or 0 V . We cannot simply let an input float if we want 0 V (float inputs are
considered to be of logic 1) . The correct wiring is indicated in the following figure.
Logic Indicators:
You could use either the scope or an LED (light emitting diode) to observe the output. In
this lab, we will measure the output of the logic gate using an LED. When using LEDs to
observe the output of TTL logic, be sure to put them in series with current-limiting
resistors. This limits the maximum current to around 10mA and will protect the output
ports of the gates. Such a circuit is shown in the Figure below, we can have the LED on
either when the output is high or when it is low, depending on which configuration we
use.
There are two configurations for LED connection: 1. Common Cathode: where the LED
will turn ON when the output of logic 1 and OFF at logic 0. 2. Common Anode: where
the LED will turn OFF when the output of logic 1 and ON at logic 0. In fact, we could
also connect LEDs to the inputs to the gate as well . In such a case, we could easily read
the truth table for our logic gates.
Common Cathode configuration
Common Anode configuration
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